Structural, transport, magnetic and thermal properties of La[sub 0.7]Ca[sub 0.24]Sr[sub 0.06]MnO[sub 3] single crystal

Abstract

La0.7Ca0.24Sr0.06MnO3 single crystals with high quality have been prepared by using floating zone technique. The structural, transport, magnetic and thermal properties of the hole doped La0.7Ca0.24Sr0.06MnO3 single crystal, have been studied using various experimental techniques. The resistivity data shows the metal to insulator transition (MI) occurs at TMI = 281 K along the c‐axis and TMI = 270 K along the ab‐plane. It is observed that the TMI data is higher along the C‐axis as compared to that in the ab‐plane, thus indicating more favourable hoping of electrons is along the c‐axis. This MI transition and large magnetoresistance peak 79% is closely near to the ferromagnetic—paramagnetic transition Tc, which was confirmed from the magnetization data (at ∼275 K), it was also confirmed from the ac susceptibility data (at ∼275 K) and the specific heat data (at ∼270 K), which in term is indicative of the onset of long range order. The entropy change associated with this transition is found to be 2.3 J/mol K. For bolometric applications point of view, the temperature coefficient of resistance (TCR) along ab‐plane is found ∼23%K−1.